• Title/Summary/Keyword: An oil pressure

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Numerical study on the foam spraying for AFDSS applicable to initial fire suppression in large underground spaces (지하대공간 초동 화재진압에 적용가능한 자율형 소화체계의 폼 분사 해석 기법 연구)

  • Park, Jinouk;Yoo, Yongho;Kim, Whiseong
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.23 no.6
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    • pp.503-516
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    • 2021
  • Autonomous fire detection and suppression system requires advanced technology for complex detection technology and injection/control technology for accurate hitting by fire location. Also, foam spraying should be included to respond to oil fires. However, when a single spray monitor is used in common, water and foam spray properties appear different, so for accurate fire suppression, research on the spray trajectory and distance will be required. In this study, experimental studies and numerical analysis studies were combined to analyze the foam spray characteristics through the spray monitor developed for the establishment of an autonomous fire extinguishing system. For flow analysis of foam injection, modeling was performed using OpenFOAM analysis software, and the commonly used foaming agent (Aqueous Film-Forming Foam) was applied for foam properties. The injection distance analysis was performed according to the injection pressure and the injection angle according to the form of the foam, and at the same time, the results were verified and presented through the injection experiment.

Management of the Development of Insecticide Resistance by Sensible Use of Insecticide, Operational Methods (실행방식 측면에서 살충제의 신중한 사용에 의한 저항성 발달의 관리)

  • Chung, Bu-Keun;Park, Chung-Gyoo
    • Korean journal of applied entomology
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    • v.48 no.2
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    • pp.123-158
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    • 2009
  • An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.

The Effects of Aroma Self Massage in Hands on Pain, Depressive Mood and Anxiety in Breast Cancer Patients (유방암 환자의 통증, 우울 및 불안 증상 조절에 아로마 자가 치료의 효과)

  • Sohn, Keun-Joo;Kim, Myung-Ja;Lee, June-Young;Lee, Jae-Bok;Kim, Su-Hyun;Kim, Jong-A;Jung, Hoe-Hyun;Choi, Seung-Wan;Choi, Youn-Seon
    • Journal of Hospice and Palliative Care
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    • v.8 no.1
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    • pp.18-29
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    • 2005
  • Purpose: Aroma therapy is one modality of alternative medicine. It was well known to have an analgesic, antidepressive and anxiolytic effects. This study is designed to investigate the effect of aroma self hand massage on vital signs, pain, depression, anxiety and stress in breast cancer patients. Methods: 32 female patient over 20 years old were divided into two groups by a non-blinded randomized controlled method. Patient in the aroma group (n=15) massaged their hands twice a day using aroma oil by themselves in their home for 2 weeks. However, those in control group (n=17) had not received my intervention during the study periods. Pain intensity, state anxiety, depression and stress of subjects were evaluated three times (0, 1, 3 weeks) using Visual Analogue Scale (VAS, $0{\sim}10cm$), State Trait Anxiety Inventory (STAI), Beck Depression Inventory Scales (BDIS), Brief Encounter Psychosocial Instrument (BEPSI revised edition). Also the change of patients' accompanying symptoms after aroma massage were analyzed using a structured questionnaire. Results: Pain Intensity decreased in the aroma group compared with control group (VAS changes $-0.83{\pm}1.01\;vs\;0.38{\pm}0.86$, P=0.005). The numbers of accompanying symptoms (P=0.044), depression score (P=0.001) and anxiety score (P=0.008) were significantly decreased in the aroma group, while in control group they increased after 2 weeks. However, the stress score showed no significant changes in both groups ($0.05{\pm}0.85\;vs\;0.04{\pm}0.20$, P=0.1519). The depression, anxiety and stress score showed negative correlation with compliance of aroma massage, but statistically no significant. The systolic blood pressure was a little increased in aroma group ($4.53{\pm}14.43\;vs\;0.0{\pm}7.22$, P=0.026), but was not significant clinically. Patients in the aroma group complained of several symptoms such as headache (20%), paresthesia (6.75%) and nausea (6.7%). However, there were no drop-out patients for those side effects. Conclusion: Aroma self massage during two weeks in breast cancer patients alleviates the pain intensity, depression and anxiety significantly.

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